Re: pg_dump locking info

On 15 August 2010 10:47, Thom Brown <thom@linux.com> wrote:
> On 15 August 2010 10:38, Thom Brown <thom@linux.com> wrote:
>> On 15 August 2010 10:29, Thom Brown <thom@linux.com> wrote:
>>> On 15 August 2010 10:01, Thom Brown <thom@linux.com> wrote:
>>>> Is this right?  I'm looking at
>>>> http://www.postgresql.org/docs/current/static/backup-dump.html
>>>>
>>>> It says, "pg_dump does not block other operations on the database
>>>> while it is working. (Exceptions are those operations that need to
>>>> operate with an exclusive lock, such as most forms of ALTER TABLE.)"
>>>>
>>>> So pg_dump actually performs an ALTER TABLE sometimes? :S
>>>>
>>>
>>> And whilst I was perusing the docs, I also noticed this on
>>> http://www.postgresql.org/docs/current/static/backup.html
>>>
>>> "Each has its own strengths and weaknesses. Each is discussed in turn below."
>>>
>>> That sentence is at the bottom of the page.  It would make sense in a
>>> PDF, but might be a confusing in section-by-section HTML
>>> documentation.
>>>
>>
>> Another thing I noticed, going back to
>> http://www.postgresql.org/docs/current/static/backup-file.html , is
>> that it makes no mention of the fact that file system level backups
>> are useless if being used to restore in a different major version.
>> Maybe "There are two restrictions, however, which make this method
>> impractical, or at least inferior to the pg_dump method" should be
>> changed to "There are three..." and add the point that
>> pg_dump/pg_dumpall is mostly immune to such limitations.
>>
>
> In the docs for version 9.0, I think the following from
> http://www.postgresql.org/docs/9.0/static/migration.html should be
> updated to make mention of streaming replication:
>
> "It is also possible to use replication methods, such as Slony, to
> create a standby server with the updated version of PostgreSQL."
>
> Of course, this page doesn't make any mention of pg_upgrade for
> upgrading from 8.3+ and probably should.
> --

Also on http://www.postgresql.org/docs/9.0/static/continuous-archiving.html

"Such dumps are logical and do not contain enough information to used
by WAL reply."

s/to used by WAL reply/to be used by WAL replay/

--
Thom Brown
Registered Linux user: #516935